tpm: suppress durations sysfs output if not read

Suppress the output in the 'durations' sysfs entry if they were not read
during driver initialization. This is similar to other sysfs entries
that return nothing if for some reason sending the commands to the TPM
fails.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Stefan Berger 2011-08-23 08:52:10 -04:00 committed by James Morris
parent 8ad346c62a
commit 403d1d0319

View file

@ -963,6 +963,9 @@ ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
{
struct tpm_chip *chip = dev_get_drvdata(dev);
if (chip->vendor.duration[TPM_LONG] == 0)
return 0;
return sprintf(buf, "%d %d %d [%s]\n",
jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),